1. Field of the Invention
The present invention relates to a fluorine-containing curable composition, more specifically a three-liquid or two-liquid type curable composition which cures more rapidly at room temperature, compared to conventional ones, on account of incorporation of a fluorine-containing alcohol.
2. Description of the Prior Art
Epoxy resins cure easily at a temperature of from room temperature to about 100° C., without causing by-products of a low molecular weight in curing. Accordingly, they are used widely in molded articles, sealants, and adhesives. However, because the epoxy resins show poor solvent resistance and chemical resistance, they are unsuitable to applications where they might be in contact with chemicals.
Meanwhile, fluorine-containing compounds, especially perfluoro-polyethers, have excellent resistance to solvents and to chemicals, and are used in curable compositions. For example, Japanese Patent Application Laid-Open No. 08-199070/1996 discloses a composition to be cured via a hydrosilylation reaction between a perfluoro-polyether compound having a terminal vinyl group and a compound having an Si—H group. Japanese Patent Application Laid-Open No. 09-077777/19967 discloses a perfluoro-polyether composition curable via a condensation reaction. However, the former has a problem that properties of a resultant cured material, such as chemical resistance, vary largely, depending upon species and amounts of a curing catalyst and a reaction controlling agent, because the hydrosilylation reaction is carried out at or below a temperature of 100 degrees Centigrade. The latter composition may cause an environment concern because low molecular weight by-products occur in the condensation reaction, such as alcohols and ketones.
Japanese Patent Application Laid-Open No. 11-092547/1999 discloses a curable composition containing a perfluoro-polyether compound having secondary amino groups at both ends of the fluoro-polyether and a fluorine-containing compound having at least three epoxy groups in a molecule. That curable composition is curable even at room temperature to give a cured material which shows a small change in volume in various solvents and high resistance to solvents and chemicals. However, its curing rate at room temperature is not satisfactory, so that improvement is desirable.